Method for dynamically allocating network adapters to communication channels for a multi-partition computer system

ABSTRACT

In an arrangement comprising a partitioned computer system and a switch with multiple adapters, wherein adapters are combined to form channels on respective partitions, a method is provided for dynamically changing the configuration of channels to which some of the adapters are assigned. The method allows better utilization for over-all network bandwidth. In one embodiment, the method includes initially allocating the adapters to establish at least one communication channel between each partition and the switch, wherein one or more adapters are allocated to each channel. Metric data is acquired for each channel during a time period, wherein the metric data indicates bandwidth utilization of respective channels. The metric data is evaluated to detect a first channel that under-utilizes available bandwidth when a second channel is over-utilizing available bandwidth. Adapters are reallocated from the first channel to the second channel by leveraging advanced Operating System and firmware support for dynamic adapter configuration, following detection of such event.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention disclosed and claimed herein generally pertains to amethod for a computer system that comprises multiple partitions, whereina switch having multiple adapters is also provided to connect thecomputer system to the Ethernet or other external network. Moreparticularly, the invention pertains to a method for the aboveconfiguration, wherein the method dynamically allocates the adapters tochannels for carrying traffic between system partitions and the switch.Even more particularly, the invention pertains to a method of the abovetype wherein the adapters are selectively assigned to and released fromrespective channels, in order to improve utilization of availablenetwork bandwidth.

2. Description of the Related Art

There is currently a strong demand for high-end computer systems thatcan provide great flexibility. Systems of this type include for examplethe Central Electronic Complex (CEC), a product of InternationalBusiness Machines Corporation (IBM), which is partitioned to includemultiple multichip-based processing units. In such systems,administrators seek increasing ability to manage precious systemresources such as network bandwidth.

In partitioned systems of the above type, it is common to provide accessto an external network by means of a switch having multiple networkadapters. Each adapter is associated with a corresponding port includedin the switch, and the adapters are used in establishing channelsbetween the switch and respective system partitions. If the network isan Ethernet network, the adapters are referred to as Ethernet adapters,and established channels comprise EtherChannels.

Moreover, in using a computer system of the above type, it is common toconfigure a Hardware Management Console (HMC) to manage the system. TheHMC can also be used by a system administrator to form channels for thepartitions from the adapters. In other cases, other control hosts likeIntegrated Virtualization Manager (IVM) can be used to set upEtherChannels. In some other cases (for example IBM AIX and Virtual I/OServer, administrator can use Operating System facilities to createEtherChannels. More particularly, taking advantage of currentlyavailable network port aggregation technologies, such as EtherChannel orIEEE 802.3ad Link Aggregation, several Ethernet adapters can beaggregated together to form a single pseudo Ethernet device. Forexample, two actual or physical Ethernet adapters, identified as ent0and ent1, can be aggregated into a single logical device, identified asadapter or EtherChannel ent3. The logical adapter ent3 would then beconfigured with an IP address, and the aggregated adapters would beconsidered by the system to be just one adapter. In addition, alladapters aggregated into a logical adapter, such as ent0 and ent1, aresimilarly treated by remote systems as if they were just one adapter.Both EtherChannel and IEEE 802.3ad Link Aggregation require support inthe switch, so that the switch will be aware of which switch portsshould be treated as a single port.

Adapter aggregation, as described above, is beneficial in that thenetwork bandwidths of all adapters included in an aggregation arecontained in a single network presence. Thus, if one adapter fails,network traffic is automatically sent on to the next available adapterwithout disruption to existing user connections. The failed adapter willlater be automatically returned to service on the EtherChannel or LinkAggregation, after it recovers. Several Unix and Linux Operating Systemssupport EtherChannel or Link Aggregation. For example, IBM AIX andVirtual I/O Server Operating Systems running on IBM Power hardwaresupports creation of EtherChannels.

Notwithstanding the benefits noted above, when currently availablepractices are used to form EtherChannels by aggregating severaladapters, the configurations that result therefore tend to be quitestatic. Static channel configurations, in turn, can prevent system usersfrom optimally using the available network bandwidth. For example, ascenario can arise, due to unprecedented workload conditions or thelike, wherein some partitions are not fully utilizing their availableEtherChannel bandwidth. At the same time, other partitions are found tobe exceeding their available total bandwidth, and are thus in need ofadditional bandwidth. Such situations are common in e-business, asexemplified by a system partition running a bookstore web application.Such system partition could undergo a sudden, very substantial increasein network traffic, upon the release of a popular book.

While an EtherChannel can load-balance network traffic between its ownassigned Ethernet adapters, there is currently no automated mechanismavailable to dynamically release Ethernet adapters from oneEtherChannel, and then assign them to a different EtherChannel.Moreover, there is no mechanism for taking such action based on asystem-level assessment of network bandwidth utilization, or on relatedRules and Policies.

SUMMARY OF THE INVENTION

The invention generally provides an arrangement wherein an HMC or thelike is configured to manage a computer system that has multiplepartitions for processing, such as a CEC. The HMC also configureschannels for respective partitions from the adapters of an associatedswitch. The HMC acquires and analyzes information regarding theworkloads of the partitions, and also regarding network bandwidthutilizations of the channels. From its analysis, the HMC may determinethat one partition is using substantially less than its availablebandwidth, whereas another partition has reached its maximum bandwidthand is getting more requests to be served. Accordingly, the HMC canrelease one or more adapters from the channel of the under-utilizedpartition, and assign them to the over-utilized channel on anotherpartition. In an embodiment of the invention, a method is provided thatincludes the step of initially allocating the adapters to establish atleast one communication channel between each partition and the switch,wherein one or more adapters are allocated to each of the channels.Metric data is acquired for each of the channels during a specified timeperiod, wherein the metric data is selected to indicate bandwidthutilization of respective channels during the time period. The metricdata is evaluated to detect an event that comprises a first channelunder-utilizing available bandwidth, when a second channel isover-utilizing its available bandwidth, and the first channel has aplurality of adapters allocated thereto. One or more adapters arereallocated from the first channel to the second channel by leveragingadvanced Operating System and firmware support for dynamic adaptermembership configuration, following detection of the event.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features believed characteristic of the invention are setforth in the appended claims. The invention itself, however, as well asa preferred mode of use, further objectives and advantages thereof, willbest be understood by reference to the following detailed description ofan illustrative embodiment when read in conjunction with theaccompanying drawings, wherein:

FIG. 1 is a block diagram showing components for implementing anembodiment of the invention;

FIG. 2 is a block diagram showing FIG. 1 with a modification to furtherillustrate the embodiment thereof;

FIG. 3 is a block diagram showing a computer or data processing systemthat may be used as an HMC for the embodiment of FIG. 1; and

FIG. 4 is a flowchart depicting respective steps of an embodiment of theinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, there is shown a computer system 102 of a type thatincludes multiple processor units and is divided into multiple workloadpartitions. Usefully, computer system 102 comprises a CEC product ofIBM, as described above. However, in other embodiments of the inventionother types of partitioned computer systems may alternatively be used.FIG. 1 shows system 102 provided with three partitions 104, individuallyreferred to as Partition 1-Partition 3, for illustrative purposes.

FIG. 1 shows system 102 to be part of a configuration 100, which furtherincludes an Ethernet switch 106 for connecting respective partitions 104of the system 102 to Ethernet 108, via a link 128. Switch 106 thusprovides connectivity for computer system 102 to external networks andsystems. Switch 106 is provided with ports 112, respectively identifiedas P1-P6, and is further provided with Ethernet network adapters 110,each usefully comprising a network interface card (NIC). Adapters 110are identified as ent1-ent6, and mate with ports P1-P6, respectively.

As described above, a plurality of Ethernet adapters can be combined oraggregated to form a single logical adapter, also referred to as anEtherChannel. Thus, FIG. 1 shows adapters ent1 and ent2 initiallyaggregated together to establish an EtherChannel 114 identified as ENT7.The EtherChannel ENT7 is seen to extend between switch 106 and Partition1, and is configured to carry data and other traffic there between.Similarly, FIG. 1 shows adapters ent3 and ent4 initially aggregated toform an EtherChannel 114 identified as ENT8, and further shows adaptersent5 and ent6 aggregated to form EthernetChannel ENT9. EtherChannelsENT8 and ENT9 connect Partitions 2 and 3, respectively, to switch 106.It is to be understood that while FIG. 1 shows only one EtherChannel 114connected to each partition, there can in fact be multiple EtherChannelsconnected between a partition and switch 106, to send traffic therebetween.

The adapters that belong to an EtherChannel 114 must be connected to thesame EtherChannel-enabled switch 104, as is shown by FIG. 1. This switchmust be manually configured to treat the port that belongs to anEtherChannel as an aggregated link. Traffic is distributed across theadapters 110 either in a standard way, wherein the adapter over whichthe packets are sent is chosen by an algorithm, or on a round-robinbasis. In the round-robin approach, packets are sent evenly across alladapters.

Multiple Ethernet adapters 110 are configured to form an EtherChannel114 by the operation of an HMC 116, which is connected to switch 106 andinterfaces therewith by means of a link 118. HMC 116, which may comprisea PC or other data processing system, is generally provided to managethe computer system 102. In addition, HMC 116 respectively allocatesadapters ent1-ent6 to set up EtherChannels ENT7-ENT9 as described above.Subsequently, HMC 116 may be operated, as described hereinafter infurther detail, to reallocate or reassign adapters from one channel toanother.

Referring further to FIG. 1, there is shown a Remote Monitoring andControl Interface 120 positioned between HMC 116 and respectivepartitions 104 of computer system 102. HMC 116 uses the RMC 120 tocommunicate with the partitions 104, and to control their respectiveoperations. The collating component 122 is a software component locatedat the HMC and implemented using RMC 120 interface. RMC services ordaemons should run on the operating systems in each one of thepartitions. Each component 124 comprises a monitoring component (MC),and each component 126 comprises a reporting component (RC), forcarrying out functions as described hereinafter. Both MC and RC willutilize RMC for communicating with Collating Component 122 on the HMC.

As previously discussed, the aggregation of multiple Ethernet adaptersinto a single logical entity provides an EtherChannel that has thecumulative bandwidth of all of its constituent adapters. Even so,however, the operation of a partition 104 may become so active that thedata traffic to and from the partition exceeds the total bandwidthcapacity of the partition EtherChannel. Thus, the EtherChannel isclearly being over-utilized. In accordance with embodiments of theinvention, it would be advantageous to recognize this situation, and tothen alleviate the situation by reallocating adapters fromunder-utilized Etherchannels to the EtherChannel that is beingover-utilized.

In view of these objectives, each of the components 124 of RMC 120 isconnected to a corresponding EtherChannel 114, to monitor bandwidthutilization therein. More particularly, a monitor component 124 acquirespre-specified types of metric data that will collectively indicatenetwork bandwidth utilization. One type of metric that could bemonitored for this purpose would be throughput, that is, the amount ofdata sent through the channel per second (or per other unit of time).Another type of metric would be response latency, which is the timerequired for a packet to travel from the source sending it to thedestination at which it is received. Yet another metric would be roundtrip latency, that is, the source to destination time plus thedestination to source time. Other types of metric data may be monitoredas well or alternatively, in other embodiments of the invention.

After the metric data for a channel has been acquired by a monitoringcomponent 124, the reporting component 126 connected thereto sends themetric data to collating component 122 of RMC 120, located in HMC 116.The collating component places the metric data showing bandwidthutilization for all of the partitions into a usable format or orderedarrangement or saves it in a database. Periodically, HMC 116 will querythe data provided by collating component 122, to get informationregarding the network bandwidth utilization of individual EtherChannels114. As an example, it is assumed that Partition 1 is found during thisprocedure to be utilizing only 30 per cent of its total availablebandwidth. At the same time, however, Partition 3 has reached itsmaximum bandwidth, and is receiving more requests from clients wantingservice. In view of this, HMC 116 will analyze the workloads of all thepartitions in the system 102, and will further analyze network bandwidthutilization of the EtherChannels associated with respective individualpartitions 114. Since Partition 1 is under-utilizing its bandwidth, HMC116 will act to release Ethernet adapter ent2 from the ENT7EtherChannel. By releasing only ent2 from ENT7, the MAC address of ENT7will continue to the MAC address of adapter ent1.

After adapter ent2 is released from EtherChannel ENT7, HMC 116 willinvoke a dynamic reallocation (DR) operation on Partition 3, in order todynamically add Ethernet adapter ent2 to the EtherChannel ENT9.Thereupon, EtherChannel ENT9 will aggregate three Ethernet adapters,that is, ent5, ent6 and ent2. Thus, Partition 3 will receive additionalbandwidth to better process the service requests coming from itsclients. In this new configuration the MAC address of EthernetChannelENT9 will continue to be the MAC address of adapter ent5.

Removal or addition of one (or more) adapters from one EtherChannel isaccomplished by using Operating System support. For example, IBM AIX hasimplemented Dynamic Adapter Membership which allows Ethernet adapters110 to be selectively removed from and added to EtherChannels in atransparent way, without causing any disruptions to the userconnections.

Once the adapter is removed from the EtherChannel, it has to be assignedto a different partition before it can be added to the EtherChannel.

Moving one physical adapter from one partition from another partition onthe same CEC can be achieved by using Dynamic Logical Partition (DLPAR)operation and Dynamic Re-Configuration (DR). Prior to the enablement ofDLPAR, reboot of the partition is required to add additional resourcesto a system. DLPAR increases the flexibility of logically partitionedsystems by allowing a user to dynamically add and remove processors,memory, I/O slots, and I/O drawers from active logical partitions. Auser can reassign hardware resources and adjust to changing systemcapacity demands without impacting the availability of the partition.DLPAR operations can be performed from the HMC and no reboot is requiredon the partitions. Once the adapter is assigned to another partition,the Operating System will dynamically re-configure it and make itavailable to be added to the EtherChannels it owns.

Referring to FIG. 2, there is shown the new configurations ofEtherChannels ENT7 and ENT9. Adapter ent2 is seen to be aggregated inEtherChannel ENT9 with adapters ent5 and ent6, whereas EtherChannel ENT7only includes adapter ent1. Subsequently, HMC 116 will continue tomonitor the network utilization. When the bandwidth utilization ofEtherChannel ENT9 drops below a certain threshold, HMC 116 will invoke aDR operation to dynamically release adapter ent2 from EthernetChannelENT9, and add it back to the EtherChannel ENT7 to which it belongs.Thus, by continuous monitoring, measurement and analysis of networkbandwidth utilization, HMC 116 is able to achieve optimal networkbandwidth utilization, by dynamically assigning and releasing adapters110 based on demand. This allows better utilization of over-all networkbandwidth, and will be of particular benefit in bandwidth intensiveapplications, such as multimedia, gaming and certain websites. It willbe understood that other embodiments of the invention may contain manymore Ethernet adapters per channel than those shown herein. Also, onepartition may contain more than one EtherChannel.

HMC 116 can be provided with an advanced configuration panel called“Collaboration Mode” for Ethernet adapters 110. This mode, when set,will enable HMC 116 to continuously monitor and dynamically assign orreassign Ethernet adapters 110 to EtherChannels 114 across partitions ondemand (on a single CEC system 102). Moreover, HMC 116 can be furnishedwith policies and rules, for use in guiding its selection of Ethernetadapters for assignment and reassignment to EtherChannels. A number ofpolicy types are possible, the following being representative examples:

-   -   a. For some EtherChannel configurations, it is possible to        specify a policy in such a way that its associated Ethernet        adapters will never be removed during its lifetime.    -   b. For some partitions, a policy can be specified that all        EtherChannels are static and cannot be modified during its        runtime.    -   c. For some partitions, a policy can be specified that its        Ethernet adapters on a particular EtherChannel can be released        only if its bandwidth utilization is less than 25%.    -   d. For some partitions, a policy can be specified that Ethernet        adapters can be released when bandwidth utilization drops below        30% but should be reassigned when the bandwidth utilization        reaches 60%.    -   e. We can implement a lease scheme for virtually loaning        Ethernet adapters to other EtherChannels. The lease has to be        renewed every x minutes, after which the Ethernet adapter will        be removed and reassigned to the original EtherChannel to which        it belongs.

Referring to FIG. 3, there is shown a block diagram of a generalizedcomputer or data processing system 300 which may be adapted for use asthe Hardware Management Console 116 in the configuration 100 shown inFIGS. 1 and 2. Data processing system 300 exemplifies a computer, inwhich code or instructions for implementing the processes of the presentinvention may be located. Data processing system 300 usefully employs aperipheral component interconnect (PCI) local bus architecture, althoughother bus architectures such as Accelerated Graphics Port (AGP) andIndustry Standard Architecture (ISA) may alternatively be used. FIG. 3shows a processor 302 and main memory 304 connected to a PCI local bus306 through a Host/PCI bridge 308. PCI bridge 308 also may include anintegrated memory controller and cache memory for processor 302.

Referring further to FIG. 3, there is shown a local area network (LAN)adapter 312, a small computer system interface (SCSI) host bus adapter310, and an expansion bus interface 314 respectively connected to PCIlocal bus 306 by direct component connection. SCSI host bus adapter 310provides a connection for hard disk drive 316, and also for CD-ROM drive318.

An operating system runs on processor 302 and is used to coordinate andprovide control of various components within data processing system 300shown in FIG. 3. The operating system may be a commercially availableoperating system such as Windows XP, which is available from MicrosoftCorporation. Instructions for the operating system and for applicationsor programs are located on storage devices, such as hard disk drive 316,and may be loaded into main memory 304 for execution by processor 302.

Referring to FIG. 4, there are shown steps for a procedure summarizingan embodiment of the invention. Initially, the HMC allocates adapters toconfigure channels for respective partitions, as described above andshown by step 402. At step 404, metric data pertaining to bandwidthutilization is acquired, such as by means of components 124 and 126described above, and the data is periodically analyzed by the HMC. Asshown by step 406, if the metric data indicates that no channel isover-utilized, the procedure of FIG. 4 is ended. However, if a givenchannel is over-utilized, it is necessary to determine whether there areany under-utilized channels, in accordance with step 408. If there areno such under-utilized channels, the procedure is ended.

As shown by step 410, if there is one or more under-utilized channels,it must be determined whether policies in effect would allowreassignment of adapters, from any of the under-utilized channels to thegiven channel. If not, the procedure is again ended. Otherwise, one ormore adapters are allocated from an under-utilized channel to the givenchannel, in accordance with step 412.

The invention can take the form of an entirely hardware embodiment, anentirely software embodiment or an embodiment containing both hardwareand software elements. In a preferred embodiment, the invention isimplemented in software, which includes but is not limited to firmware,resident software, microcode, etc.

Furthermore, the invention can take the form of a computer programproduct accessible from a computer-usable or computer-readable mediumproviding program code for use by or in connection with a computer orany instruction execution system. For the purposes of this description,a computer-usable or computer readable medium can be any tangibleapparatus that can contain, store, communicate, propagate, or transportthe program for use by or in connection with the instruction executionsystem, apparatus, or device.

The medium can be an electronic, magnetic, optical, electromagnetic,infrared, or semiconductor system (or apparatus or device) or apropagation medium. Examples of a computer-readable medium include asemiconductor or solid state memory, magnetic tape, a removable computerdiskette, a random access memory (RAM), a read-only memory (ROM), arigid magnetic disk and an optical disk. Current examples of opticaldisks include compact disk—read only memory (CD-ROM), compactdisk—read/write (CD-R/W) and DVD.

A data processing system suitable for storing and/or executing programcode will include at least one processor coupled directly or indirectlyto memory elements through a system bus. The memory elements can includelocal memory employed during actual execution of the program code, bulkstorage, and cache memories which provide temporary storage of at leastsome program code in order to reduce the number of times code must beretrieved from bulk storage during execution.

Input/output or I/O devices (including but not limited to keyboards,displays, pointing devices, etc.) can be coupled to the system eitherdirectly or through intervening I/O controllers.

Network adapters may also be coupled to the system to enable the dataprocessing system to become coupled to other data processing systems orremote printers or storage devices through intervening private or publicnetworks. Modems, cable modem and Ethernet cards are just a few of thecurrently available types of network adapters.

The description of the present invention has been presented for purposesof illustration and description, and is not intended to be exhaustive orlimited to the invention in the form disclosed. Many modifications andvariations will be apparent to those of ordinary skill in the art. Theembodiment was chosen and described in order to best explain theprinciples of the invention, the practical application, and to enableothers of ordinary skill in the art to understand the invention forvarious embodiments with various modifications as are suited to theparticular use contemplated.

1. In a configuration provided with a computer system having multipleprocessor partitions, and further provided with a switch having multipleadapters, a method comprising the steps of: initially allocating saidadapters to establish at least one communication channel between eachpartition and said switch, wherein one or more adapters are allocated toeach of said channels; acquiring metric data for each of said channelsduring a specified time period, wherein said metric data is selected toindicate bandwidth utilization of respective channels during said timeperiod; evaluating said acquired metric data to detect an event thatcomprises a first channel under-utilizing its available bandwidth, whena second channel is over-utilizing its available bandwidth and saidfirst channel has a plurality of adapters allocated thereto; andreassigning one or more adapters from said first channel to said secondchannel, following detection of said event.
 2. The method of claim 1,wherein: a plurality of adapters allocated to a channel are aggregatedto form a single logical adapter that comprises the channel.
 3. Themethod of claim 1, wherein: each of said adapters comprises an Ethernetadapter, and each of said channels comprises an EtherChannel.
 4. Themethod of claim 1, wherein: said acquisition of metric data includes atleast acquiring data that pertains to metric data types respectivelyidentified as throughput and response latency.
 5. The method of claim 1,wherein: said evaluating and assigning steps are carried out by means ofa control host, wherein said control host can be a Hardware ManagementConsole or an Integrated Virtualization Manager.
 6. The method of claim5, wherein: said Hardware Management Console is furnished withpre-specified policies for use in selecting an adapter for reassignmentfrom one channel to another channel.
 7. The method of claim 1, wherein:each of said partitions is provided with a data monitoring component anda reporting component, the monitoring and reporting components of agiven partition being used to monitor and report metric data thatpertains to network utilization of a channel used by the givenpartition.
 8. The method of claim 7, wherein: said monitoring andreporting components for each partition are respectively included in aRemote Monitoring and Control interface that extends between saidcomputer system and said HMC, and provides communication there between.9. The method of claim 1, wherein: said reassigned adapters arereassigned back to said first channel from said second channel, whenutilization of said second channel drops below a specified threshold.10. The method of claim 1, wherein: a Dynamic Adapter Membership is usedto allow transparent reassignments of said adapters from one channel toanother.
 11. The method of claim 1, wherein: a Dynamic Logical PartitionOperation (DLPAR) and Dynamic Re-Configuration(DR) is used to allowtransparent reassignment of adapters from one partition to another. 12.In a configuration provided with a computer system having multipleprocessor partitions, and further provided with a switch having multipleadapters, a computer program product in a computer readable mediumcomprising: first instructions for initially allocating said adapters toestablish at least one communication channel between each partition andsaid switch, wherein one or more adapters are allocated to each of saidchannels; second instructions for acquiring metric data for each of saidchannels during a specified time period, wherein said metric data isselected to indicate bandwidth utilization of respective channels duringsaid time period; third instructions for evaluating said acquired metricdata to detect an event that comprises a first channel under-utilizingits available bandwidth, when a second channel is over-utilizing itsavailable bandwidth and said first channel has a plurality of adaptersallocated thereto; and fourth instructions for reassigning one or moreadapters from said first channel to said second channel, followingdetection of said event.
 13. The computer program product of claim 12,wherein: said acquisition of metric data includes at least acquiringdata that pertains to metric data types respectively identified asthroughput and response latency.
 14. The computer program product ofclaim 12, wherein: said evaluating and reassigning steps are carried outby means of a Hardware Management Console that is included in saidconfiguration, and that is furnished with pre-specified policies for usein selecting an adapter for reassignment from one channel to anotherchannel.
 15. The computer program product of claim 12, wherein: saidreassigned adapters are reassigned back to said first channel from saidsecond channel, when utilization of said second channel drops below aspecified threshold.
 16. In a configuration provided with a computersystem having multiple processor partitions, and further provided with aswitch having multiple ports, apparatus comprising: adaptersrespectively corresponding to said switch ports, and disposed forinitial allocation to establish at least one communication channelbetween each partition and said switch, wherein one or more adapters areallocated to each of said channels; components connected to acquiremetric data for each of said channels during a specified time period,wherein said metric data is selected to indicate bandwidth utilizationof respective channels during said time period; and a HardwareManagement Console (HMC) for evaluating said acquired metric data todetect an event that comprises a first channel under-utilizing itsavailable bandwidth, when a second channel is over-utilizing itsavailable bandwidth and said first channel has a plurality of adaptersallocated thereto, said HMC further operative to reassign one or moreadapters from said first channel to said second channel, followingdetection of said event.
 17. The apparatus of claim 16, wherein: each ofsaid adapters comprises an Ethernet adapter, and each of said channelscomprises an EtherChannel.
 18. The apparatus of claim 16, wherein: saidHardware Management Console is furnished with pre-specified policies foruse in selecting an adapter for reassignment from one channel to anotherchannel.
 19. The apparatus of claim 16, wherein: said acquiringcomponents comprise a monitoring component and a reporting component foreach partition, the monitoring and reporting components of a givenpartition being used to monitor and report metric data that pertains tonetwork utilization of a channel used by the given partition.
 20. Theapparatus of claim 19, wherein: said monitoring and reporting componentsfor each partition are respectively included in a Remote Monitoring andControl interface that extends between said computer system and saidHMC, and provides communication there between.